To evaluate the current pneumococcal vaccine in the institutionalized elderly by observing vaccine-associated reactions and subsequent incidence and etiology of pneumonias and pneumonia-associated mortality. We plan to study approximately 1,900 patients from 4 different chronic-care institutions. The study population will consist of approximately 700 patients who have been institutionalized for less than 400 days at the time of vaccination and additional 1,200 new admissions who will be entered over the next 12 months. These patients will be selected because they are at an especially high risk for acquiring pneumococcal pneumonia; they will be followed for 1-2 years (depending on their data of entry) or until discharge. Prior to vaccination extensive in-services will be performed to insure that all respiratory infections will be investigated by clinical examination, chest roentgenograms, and cultures of respiratory secretions and blood prior to starting antimicrobials. Special studies to identify and recover S. pneumoniae (pneumococcus) will include direct Quellung reaction with omniserum and counterimmunoelectrophoresis of respiratory secretions, selective-inhibitory media and typing of all isolates with Danish monovalent typing sera. Vaccinees will be observed for immediate-acute, local and constitutional reactions. This population will be exposed to approximately 700 patient years of risk per year of developing a pneumonia. Information will be obtained on the incidence of pneumonia, bacteremia, and mortality (total pneumococcal and pneumococcal due to sera types contained in the vaccine) per 1,000 patient years; the etiology of all radiologically confirmed pneumonias and the pneumoccal types associated with respiratory events, radiologically confirmed pneumonias and pneumonia-associated deaths. Surveillance figures collected at the Monroe Community Hospital for four years prior to vaccination will be used for comparison.